1. Field of the Invention
The present invention relates generally to a kneading or mixing apparatus used to knead, mix or compound polymeric materials and, more specifically, to an apparatus including a liner secured within a kneader housing.
2. Description of the Related Art
Kneaders or mixing machines are typically used to knead, mix or compound a polymeric material. Typically, such machines include a housing that forms a mixing chamber. Inserted into the mixing chamber is a shaft or screw member that both rotates and reciprocates to mix material contained or placed within the mixing, chamber. To aid in the kneading, or mixing, process, a plurality of kneader or mixing, pins extend through the housing, and inwardly into the mixing chamber. The pins cooperate with the screw member through notches in the screw member to further agitate or "work" the polymeric material to complete the mixing or kneading process.
Depending, upon the type of material sought to be mixed or compounded, the number of kneader pins used may vary. It also is known to vary the length of the pins; i.e., the amount of pin extending into the mixing chamber may also change. Arrangement of the pins is also a factor to be considered regarding the mixing or kneading process. Arrangement of the pins, however, is limited by heating/cooling passages extending through the housing. Further, as the pins extend through the housing, it is possible that the mixture or kneaded material may leak through the kneader pin/housing interface. Finally, changing the kneader pins can be a time-consuming and difficult chore resulting in downtime for the kneader or mixing machine.
The prior art discloses several kneader/extruder assemblies wherein the kneader pins are attached to and supported by a cylindrical sleeve placed within the housing.